High Slope Stability Research Articles

Influence of Rainfall Infiltration on Stability of Granite Residual Soil High Slope

The seepage evolution characteristics and stability change rule of granite residual soil inside the high cutting slope under the action of rainfall infiltration were studied. Based on the saturated-unsaturated seepage theory, the numerical simulation of the rainwater infiltration path inside the granite residual soil slope was carried out under the condition of rainwater infiltration. The evolution characteristics of the seepage field of the granite residual soil cutting high slope under the condition of rainfall infiltration were revealed, and the influence of the rainwater infiltration on the stability of the granite residual soil slope was mainly studied. The research results show that with the accumulation of rainfall infiltration, the pore water pressure of the granite residual soil slope increases continuously, and the pore water pressure of the soil below the platform increases the fastest. With the increase in elevation, the water content of the slope presents a wave crest distribution. In the early stage of rainfall, the seepage velocity vector distribution on the slope surface is relatively uniform. In the middle stage of rainfall, the seepage velocity vector is the most dense at the platform, and the rainwater migration rate is accelerated. In the later stage of rainfall, the infiltrated rainwater at the slope angle of the first-level slope spreads to the surrounding area. With the continuous rainfall, the slope stability safety factor gradually decreased unevenly, and after the rainfall stopped, it gradually increased with the rainwater infiltration.

Application of combined terrestrial laser scanning and unmanned aerial vehicle digital photogrammetry method in high rock slope stability analysis: A case study

Recent advancements in remote sensing techniques have made it possible to overcome the risky issues using conventional methods and have opened up new opportunities for collecting data on discontinuity characteristics. This research compares the application of a Terrestrial Laser Scanner (TLS) and Unmanned Aerial Vehicle (UAV) in rock slope stability analysis. Two case studies, Ulu Choh Quarry and Jelapang Rock Slope are analysed using Kinematic Analysis and Slope Mass Rating (SMR) to depict rock through the 3D point cloud. The techniques are compared with the hand mapping method concerning the accuracy of the data acquisition in assessing the rock slope. The standard deviation for the dip and dip direction between digital capture and hand mapping is 2.97° and 2.86°, which falls under the acceptable tolerance limit. The integration of UAV and TLS also generates excellent clear point cloud data from the top to the toe of the slope.

Deep-Seated Deformation Mechanisms of Excavated Slope and Control Methods: A Case Study

High slope stability control is a crucial technical issue in water conservancy and hydropower project construction. This issue is relevant throughout the entire engineering-related survey, design, construction, and operation process. This paper reports a recent case in which significant deep-seated deformation occurred during slope excavation. Several unfavorable structural surfaces were revealed throughout the slope’s undercutting process, particularly fault fz39, which ran diagonally through the entire slope from top to bottom. On the slope surface, damage such as cracking, bulging, and local slippage appeared. The measured value of multipoint displacement meters increased in a stepwise pattern with each blast, and the maximum measured value exceeded 100 mm. The studied slope’s whole excavation and reinforcement process is described in detail. We analyzed the deformation mechanism of the excavation slope by combining the geological conditions, real-time safety monitoring findings, and site deformation characteristics. The slope reinforcement scheme was optimized based on the preceding analyses. We used a three-dimensional numerical calculation program to simulate the slope excavation and unloading process to reproduce the current mechanical state of the slope, evaluate the reinforcement measures, and provide a useful reference for decision making. The analysis shows that the deformation behavior of the studied slope is closely related to fault fz39 and fracture L920, and presents a typical wedge failure mode. The deep-seated deformation of the excavation slope occurs at the junction of the wedge and bedrock, which is mainly affected by unfavorable geological structure surfaces, excavation unloading, and blasting vibration. The reinforcement scheme of unloading at the top of the slope and large-tonnage cables are established. The numerical analysis results showed that the design of the slope reinforcement measures was appropriate and ensured slope stability. The work described in this paper deepens our understanding of the occurrence of large deep-seated deformation on the structural-controlled slope under the action of excavation and improves the design philosophy.

Study on Three-Dimensional Dynamic Stability of Open-Pit High Slope under Blasting Vibration

AbstractThe propagation process of blasting vibration has always been a difficult problem affecting the stability of high slopes in open-pit mines. Taking the Jianshan Phosphorus Mine as the research background, combined with engineering geological investigation, field blasting test, blasting vibration monitoring, numerical simulation technology, and theoretical analysis, the three-dimensional dynamic stability of the adjacent high slope after blasting vibration was systematically studied. In our study, a small-diameter buffer shock-absorbing blasting technology near the slope was proposed, which greatly improved the production efficiency. Through regression analysis of a large amount of vibration test data, the law of blasting vibration propagation in Jianshan stope and Haifeng stope was obtained. In addition, by establishing four three-dimensional geomechanical numerical models, the slope’s own frequency, damping characteristics, and dynamic response acceleration distribution after detonation were studied, respectively. On the other hand, under the action of Ei Centro wave with 8-degree seismic intensity, the maximum total acceleration and maximum total displacement of the slope were calculated and analyzed. Both the explosion unloading of the 8-degree earthquake and the Ei Centro wave simulation results showed that the high slope near the Jianshan Phosphorus Mine was generally in a stable state. Thus, this study can provide technical support and theoretical guidance for mine blasting.

Stability Analysis of Loess High Slope under Dynamic Compaction Based on Matrix Discrete Element Method

In order to investigate the safety and stability of loess high slope under dynamic ramming, the MatDem software was used to simulate the process of heavy rammer compacting the spot which was 11 m away from the toe of loess high slope. The rammer was applied with different energies of 10000 kN·m, 8000 kN·m, and 6000 kN·m. In this way, the safety and stability of slope under the action of different dynamic tamping energies can be determined. The results show that the loess high slope presented circular landslide damage by dynamic compaction. Under the same ramming times, with the decrease of ramming energy, the damage degree of loess high slope gradually reduced. According to the displacement value of different monitoring points, the large horizontal and vertical displacement points in landslide were obtained. When the ramming energy was 10000 kN·m and 8000 kN·m, the maximum horizontal displacements were 15.45 m and 10.72 m, and the maximum vertical displacements were 17.43 m and 11.91 m. When the ramming energy was 6000 kN·m, the soil at the bottom of slope would produce slight vibration. Considering the actual project, when the ramming energy was 10000 kN·m and 8000 kN·m, the minimum safe distance was recommended to be 25 m and 20 m. When the ramming energy was 6000 KN·m, the slope remained stable as a whole, and the minimum safe distance suggested should not be less than 11 m. A safety distance of collapse of loess high slope under dynamic compaction was determined, which provided a strong safety guidance for loess high slope construction under dynamic compaction.

Stability Analysis of Blasting Excavation for High Rock Slope of Highway Reconstruction and Expansion

To analyze the stability of high rock slopes under millisecond blasting in the paper, time‐history curves of millisecond blasting dynamic loads are established based on field data from the reconstruction and extension project of the Beijing‐Shanghai Highway. Numerical simulations and field monitoring data are used to study the dynamic response characteristics of the slope stress, displacement, velocity, and safety factor at different times. The results show that the local shear stress near the blasting area is greater than the shear strength of the rock mass, which has a good effect on precracking. Additionally, the peak vibration law of the particles near the blasting area is found to change synchronously with the application of the dynamic blast load; as the distance increases, the law gradually weakens and peak vibration occurs only near the maximum value. Moreover, the safety factor of the slope exhibits a decreasing periodic variation. When the dynamic blast load F reaches the maximum load Fmax and 0.6 Fmax, the corresponding safety factor reaches the minimum load.

Improving Slope Stability in Open Cast Mines via Machine Learning based IoT Framework

Slope stability has been a matter of concern for most geologists, mainly due to the fact that unstable slopes cause a greater number of accidents, which in turn reduces efficiency of mining operations. In order to reduce the probability of these slope instabilities, methods like tension crack mapping, inclinometer measurements, time domain reflectometry, borehole extensometers, piezometer, radar systems and image processing systems are deployed. These systems work efficiently for single site slope failures, but as the number of mining sites increase, dependency of one site slope failure on nearby sites also increases. Current systems are not able to capture this data, due to which the probability of accidents at open cast mines increases. In order to reduce this probability, a high efficiency internet of things (IoT) based continuous slope monitoring and control system is designed. This system assists in improving the efficiency of real-time slope monitoring via usage of a sensor array consisting of radar, reflectometer, inclinometer, piezometer and borehole extensometer. All these measurements are given to a high efficiency machine learning classifier which uses data mining, and based on its output suitable actions are taken to reduce accidents during mining. This information is dissipated to nearby mining sites in order to inform them about any inconsistencies which might occur due to the slope changes on the current site. Results were simulated using HIgh REsolution Slope Stability Simulator (HIRESSS), and an efficiency improvement of 6% is achieved for slope analysis in open cast mines, while probability of accident reduction is increased by 35% when compared to traditional non-IoT based approach.

Study on the Influence of Various Rainfall Types on the Stability of High and Steep Slopes

Taking the high and steep slope of a ski resort as the background, in order to ensure the structural safety of the slope in the subsequent complex rainfall environment, the calculation principle of unsaturated soil slope stability is summarized, and the parameter interaction analysis is proposed. The numerical simulation method is used to study the influence of various rainfall types on slope stability; combined with a multiparameter combination, the slope stability is analyzed. The results show that different types of rainfall have a significant impact on the safety factor of the slope, the safety factor of the slope under the front rainfall type is the smallest, the minimum value is 1.38, and the front rainfall mostly occurs in the late summer, so it is necessary to avoid construction in the late summer or do a good job of safety monitoring in the late summer. Through setting monitoring points, it is found that the pore water pressure of the three positions from small to large is in the order of slope toe<slope middle<slope top, and the pore water pressure at the slope toe is basically 0 kPa. At this time, the matric suction at the slope toe is the minimum, so the protection should be strengthened. In the combination analysis of the four parameters, the direct effect and coupling effect of C15 are at a small level, which indicates that when the four parameters fluctuate together, the mutual coupling is not the effect of a single parameter, which provides a theoretical reference for the follow-up related research.

Retraction Note: Stability of slope rainfall condition based on GIS and nutrition intervention of football training

This paper mainly studies the problems related to the evaluation of high slope intelligent area under rainfall conditions and, through the unified design method, saturation unsaturation theory, marginal equilibrium neural network theory, and GIS, based on Fengjie area, studies the rainfall conditions and the evaluation of high and low slope stability in intelligent area. This paper provides a positive research and practice way for GIS intelligence and is establishing an intelligent regional evaluation system based on GIS platform. As the goal of high slope stability research under rainfall conditions, the intelligent regional evaluation map based on slope stability can become an important basis for Fengjie region to prevent and control global disasters. Although football training is scientific, scientific and reasonable use of nutrition intervention measures can improve the training efficiency of football players, increase the time of athletes to bear the extreme sports load, delay the fatigue of sports, and ultimately improve the performance of athletes. This study is based on the investigation and field test of nutritional intervention of football players and puts forward and proves the practical basis and empirical effect of nutritional supplements in football players. The purpose is to provide an effective basis for supporting football players’ nutritional supplements through targeted case studies. According to the research of GIS, it is applied to the slope rainfall and football training nutrition intervention, which can effectively improve the slope rainfall and football training nutrition intervention.

Study on Blasting Technology for Open-Pit Layering of Complex Mine Adjacent to High and Steep Slope

In China, mining blasting vibration has seriously threatened the safety and stability of high and steep rock slopes. In this paper, taking the east mining area of Jianshan Phosphorus Mine as the research background, combined with field survey, field blasting test, numerical simulation and theoretical analysis, we systematically studied the adjacent high-steep rock slope and the layered blasting technology of complex ore. Based on wide hole spacing blasting numerical simulation and field tests, the use of 8 × 4 m hole network parameters, oblique line hole-by-hole initiation method, detonator delay using 35 ms between holes, 65 ms between rows and 500 ms within the holes, the rock mass rate was reduced and the drilling workload was decreased. In addition, regression analysis was carried out on a large amount of vibration test data, and the attenuation law and propagation law of blasting vibration of adjacent high and steep slopes were predicted, which provided a reference for mine production blasting. By establishing a mathematical model of cumulative damage of rock mass blasting, it shows that the depth of impact of mining blasting on the slope of Jianshan open-pit was 0–3.6m, but the blasting did not cause overall damage to the adjacent high and steep slopes. In the future, this model can be used to predict rock damage caused by subsequent blasting.

Failure Mode and Characteristics of Expansive Rock and Influencing Factors of High Slope Stability

Failure Mode and Characteristics of Expansive Rock and Influencing Factors of High Slope Stability

Computational tools for the analysis of circular failure of rock slopes

Among other types of failure in slopes created by excavation or filling, circular (also referred to as rotational) type of failure plays an important role in the design and stability analysis of high rock slopes, such as those encountered in deep open pit mines. When a rock slope of significant height involves predominantly one type of jointed rock mass, the scale of the problem is frequently such that the rock mass (intact rock and rock discontinuities) can be regarded as a homogeneous isotropic material. In such case, if the rock slope is unstable and collapse occurs, circular (or rotational) failure as in failed slopes in soils is also observed for the rock slope. One main goal in practical design of deep open pit mines is to determine safe inclination angles for the pit faces to be excavated to avoid failure. Computational tools for quick assessment of the stability conditions, in particular determination of factor of safety and location of the critical circular failure surface, are useful during the preliminary stages of open pit design. Among others, such tools allow the engineer to gain insight in the role that the different variables controlling the problem have in defining the stability conditions for the rock slope. This paper provides first an overview of typical numerical techniques used to assess the stability of high rock slopes. For the case of slopes in rock masses that are assumed to obey the Mohr-Coulomb or the Hoek-Brown failure criteria, the paper discusses how application of transformation rules leads the criteria to be re-casted in dimensionless form, so when these are applied to the solution of slope problems, the results (factor of safety and coordinates that define the location of the critical circular failure surface) can be summarized in dimensionless compact forms. The paper presents then computational tools in the form of dimensionless charts and computer spreadsheets for stability analysis. These are developed from numerical limit equilibrium models that use the mentioned transformation rules. Among others, the computational tools allow the concept of mechanical similarity of rock slopes to be naturally introduced. Finally, the paper presents various rock slope examples that illustrate the use of the computational tools. In these examples, results from limit equilibrium models are also compared with results obtained with full numerical analysis, in particular with finite difference models implementing the shear strength reduction technique.

Bearing capacity behaviour of prestressed anchor cable under slope blasting excavation

The stability of high steep rock slopes directly influences the success or failure of whole engineering construction processes. Slope excavation and reinforcement with prestressed anchor cable can effectively improve the stability of the slope. However, the blasting stress waves have a great impact on the anchor cables that have been installed or are under construction. In this paper, a new simulating method of prestressed anchor cables is proposed for high steep rock slopes in consideration of the construction process and the reinforcement mechanism. And a simple simulating method of slope blasting excavation load is developed. The bearing capacity of prestressed anchor cables under slope blasting excavation is analysed via an ideal generalized slope model based on the left bank slope of the Jinping I hydropower station. The results show that the degree by which the distance from the blasting zone, the damping ratio, the maximum single-shot dose and the grade of the prestressed anchor cable impact the bearing capacity behaviours of the prestressed anchor cable decrease over time. Anchor cables are most prone to vibration failure within 5 m from the outer anchor head. The increase in tensile force is the largest on the anchor head at the slope surface. The impact of the maximum single-shot dose and damping ratio on the small-tonnage anchor cable is greater than that on the large-tonnage anchor cable. The anti-explosion performance of the large-tonnage anchor cable is better than that of the small-tonnage anchor cable. The foundations and experience needed to optimize the parameters of blasting excavation and anchor cable design for similar high-slope projects in China or other regions are presented.

Stability Assessment of High and Steep Cutting Rock Slopes with the SSPC Method

The stability of high rock slopes has become a key engineering geological problem in the construction of important projects in mountainous areas. The original slope stability probability classification (SSPC) system, presented by Hack, has made obvious progress and been widely used in rock slope stability analysis. However, the selection and determination of some evaluation indexes in the original SSPC method are usually subjective, such as intact rock strength and weathering degree. In this study, the SSPC method based on geological data obtained in the prospecting tunnels was presented and applied. According to the field survey and exploration of the prospecting tunnels, the weathering degree of the slope rock mass was evaluated. The empirical equation for the maximum stable height of the slope was applied to the slope stability evaluation in the presented SSPC method. Then, the slope stability probability of numerous cutting slopes in the sandstone unit was evaluated using the presented system. Results of the Geostudio software based on the limited equilibrium analysis of the investigated slopes were compared with the results obtained by the SSPC method. The results indicate that the SSPC method is a useful tool for the stability prediction of high and steep rock slopes.

Numerical analysis of influence of joint inclination on the stability of high rock slope with weak interlayer

In the mountainous area of southwest China, the horizontal layered steep slopes with weak intercalations are widely distributed. The stability of these slopes is often controlled by the weak intercalations and the dominant joint sets. Based on the strength reduction method, a representative numerical simulation model is established in this study, and the ubiquitous-joint model is adopted in which the properties of rock blocks and joints can both be considered, in order to analyze the influence of joint angle on slope stability and potential sliding surface of such slopes. The research results indicate that the joint inclination angle is closely related to both the safety coefficient and the potential sliding range of the slope. With the increase of joint inclination angle, the safety coefficient of the slope decreases, but the downward trend gradually becomes slower. The joint inclination angle also has an obvious influence on the sliding surface range of the horizontal layer slope with weak interlayer. The research results have certain guiding significance in the analysis of failure mechanism, hazard assessment and engineering prevention of this kind of slope.

Analysis of High Slope Seepage Influence Based on Multi-scale Measurement Data

In order to study the influence of seepage on high slope stability, the impact of drainage hole blockage on slope stability is analyzed by in-situ test technology, near-field photogrammetry and indoor test and numerical simulation.According to the groundwater monitoring of the water meter and pore pressure meter, when the drainage hole blockage exceeds 80%, the pore water pressure increases by about 13m, by 25kPa; is monitored by the steel gauge and anchor gauge. When the drainage hole blockage exceeds 80%, the shear force of the slope anti-sliding pile increases by 20%, about 30kN; analyzes the slope deformation by the near-view photography technique, when the drainage hole blockage exceeds 80%, and the slope deformation of 44mm, exceeds the slope deformation warning value of 30mm,.After theoretical calculation and numerical simulation analysis, the groundwater level and support structure under different blockage conditions. Numerical simulation results show that when the drainage hole is less than 60%, the supporting structure and slope deformation grow linearly, while when the blockage degree exceeds 80%, the support structure increases sharply, and according to the finite element strength, when the blockage degree exceeds 60%, the slope stability coefficient decreases sharply and the risk of instability.

Improving the stability of high embankment slopes on weak foundations

The article considers the issues of assessing the stability of non-standard soil-geological systems in difficult conditions. An analytical review of modern methods and tools for assessing the stability of embankment slopes is carried out. The features of the work of the embankment in the areas of the spread of permafrost are considered. The features of the design of embankments on permafrost soils with the preservation or partial thawing of frozen soils have been studied. Two versions of the calculated static schemes of sliding surfaces are presented: base - subgrade and base - subgrade - pavement. Based on the results of field studies, the physical and mechanical characteristics of the soils of the embankment and the base of the subgrade were determined, which became the basis for mathematical modeling and assessment of the stability of the embankment slopes. In software packages GeoStab and Geo5, based on the finite element method and the results of field studies, digital models of embankments were built on a weak foundation. The calculation of the stability of the system “base - subgrade” under the action of a standard uniformly distributed load has been performed. Two models of the system and the base - subgrade - road surface are considered: without cracks on the rolling strip and with cracks. It was found that coating defects affect the stability of the system only in the presence of an earthquake of medium strength and more. Recommendations for strengthening the slopes of embankments operating in difficult soil-geological conditions are given.

西宁机场高填方边坡稳定性对邻近铁路的影响分析

西宁机场高填方边坡稳定性对邻近铁路的影响分析

Precise Topographic Model Assisted Slope Displacement Retrieval from Small Baseline Subsets Results: Case Study over a High and Steep Mining Slope.

Due to the intrinsic side-looking geometry of synthetic aperture radar (SAR), time series interferometric SAR is only able to monitor displacements in line-of-sight (LOS) direction, which limits the accuracy of displacement measurement in landslide monitoring. This is because the LOS displacement is only a three dimensional projection of real displacement of a certain ground object. Targeting at this problem, a precise digital elevation model (DEM) assisted slope displacement retrieval method is proposed and applied to a case study over the high and steep slope of the Dagushan open pit mine. In the case study, the precise DEM generated by laser scanning is first used to minimize topographic residuals in small baseline subsets analysis. Then, the LOS displacements are converted to slope direction with assistance of the precise DEM. By comparing with ground measurements, relative root mean square errors (RMSE) of the estimated slope displacements reach approximately 12–13% for the ascending orbit, and 5.4–9.2% for the descending orbit in our study area. In order to validate the experimental results, comparison with microseism monitoring results is also conducted. Moreover, both results have found that the largest slope displacements occur on the slope part, with elevations varying from −138 m to −210 m, which corresponds to the landslide area. Moreover, there is a certain correlation with precipitation, as revealed by the displacement time series. The outcome of this article shows that rock mass structure, lithology, and precipitation are main factors affecting the stability of high and steep mining slopes.

Sensitivity of High Fill Slope Stability Factors under Seismic Conditions

An evaluation method based on vector similarity is introduced to determine the sensitivity of stability factors of high fill slope under seismic action in this paper. The Euclidean similarity and cosine similarity of slope stability factors are calculated. In addition, grey relational analysis method is used to calculate the case, and the three calculation results are compared. The results show that the sensitivity ranking results of high fill slope stability factors obtained by cosine similarity and grey correlation analysis are consistent, and slightly different from those obtained by Euclidean similarity. This indicates that cosine similarity method is more suitable for sensitivity evaluation of high fill slope stability factors than Euclidean similarity method.